Trabajo en el laboratorio los autores ha sido apoyado por el USDA / CSREES / NRICGP (2007-35203-18213), NIH / CNRR (2 R01 RR17359-06), NIH / NIEHS (1 R21 ES014856-01A2) y Alberta Innova - Soluciones para la Salud.

<ol>
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L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Growth+factors+essential+for+self-renewal+and+expansion+of+mouse+spermatogonial+stem+cells.">Growth factors essential for self-renewal and expansion of mouse spermatogonial stem cells.</a> Proceedings of the National Academy of Sciences of the United States of America. 101 (47), 16489-16489 (2004).</li><li>Oatley, J. M., Avarbock, M. R., Telaranta, A. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identifying+genes+important+for+spermatogonial+stem+cell+self-renewal+and+survival.">Identifying genes important for spermatogonial stem cell self-renewal and survival.</a> Proceedings of the National Academy of Sciences of the United States of America. 103 (25), 9524-9524 (2006).</li><li>Dobrinski, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Germ+cell+transplantation+and+testis+tissue+xenografting+in+domestic+animals.">Germ cell transplantation and testis tissue xenografting in domestic animals.</a> Animal Reproduction Science. 89 (1-4), 137-137 (2005).</li><li>Dobrinski, I., Avarbock, M. R., Brinster, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transplantation+of+germ+cells+from+rabbits+and+dogs+into+mouse+testes.">Transplantation of germ cells from rabbits and dogs into mouse testes.</a> Biology of Reproduction. 61 (5), 1331-1331 (1999).</li><li>Honaramooz, A., Snedaker, A., Boiani, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sperm+from+neonatal+mammalian+testes+grafted+in+mice.">Sperm from neonatal mammalian testes grafted in mice.</a> Nature. 418 (6899), 778-778 (2002).</li><li>Rodriguez-Sosa, J. R., Dobrinski, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+developments+in+testis+tissue+xenografting.">Recent developments in testis tissue xenografting.</a> Reproduction. 138 (2), 187-187 (2009).</li><li>Dobrinski, I., Rathi, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ectopic+grafting+of+mammalian+testis+tissue+into+mouse+hosts.">Ectopic grafting of mammalian testis tissue into mouse hosts.</a> Methods in Molecular Biology. 139, 450-450 (2008).</li><li>Rodriguez-Sosa, J. R., Schlatt, S., Dobrinski, I., Seli, E., Agarwal, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Testicular+tissue+transplantation+for+fertility+preservation.">Testicular tissue transplantation for fertility preservation.</a> Fertility Preservation: Emerging Technologies and Clinical Applications. , 331-331 (2011).</li><li>Rathi, R., Honaramooz, A., Zeng, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Germ+cell+fate+and+seminiferous+tubule+development+in+bovine+testis+xenografts.">Germ cell fate and seminiferous tubule development in bovine testis xenografts.</a> Reproduction. 130 (6), 923-923 (2005).</li><li>Rathi, R., Honaramooz, A., Zeng, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Germ+cell+development+in+equine+testis+tissue+xenografted+into+mice.">Germ cell development in equine testis tissue xenografted into mice.</a> Reproduction. 131 (6), 1091-1091 (2006).</li><li>Kim, Y., Selvaraj, V., Pukazhenthi, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+donor+age+on+success+of+spermatogenesis+in+feline+testis+xenografts.">Effect of donor age on success of spermatogenesis in feline testis xenografts.</a> Reproduction, Fertility, and Development. 19 (7), 869-869 (2007).</li><li>Arregui, L., Rathi, R., Zeng, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Xenografting+of+adult+mammalian+testis+tissue.">Xenografting of adult mammalian testis tissue.</a> Animal Reproduction Science. 106 (1-2), 65-65 (2008).</li><li>Schlatt, S., Honaramooz, A., Ehmcke, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Limited+survival+of+adult+human+testicular+tissue+as+ectopic+xenograft.">Limited survival of adult human testicular tissue as ectopic xenograft.</a> Human Reproduction. 21 (2), 384-384 (2006).</li><li>Shinohara, T., Avarbock, M. R., Brinster, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=beta1-+and+alpha6-integrin+are+surface+markers+on+mouse+spermatogonial+stem+cells.">beta1- and alpha6-integrin are surface markers on mouse spermatogonial stem cells.</a> Proceedings of the National Academy of Sciences of the United States of America. 96 (10), 5504-5504 (1999).</li><li>Kanatsu-Shinohara, M., Toyokuni, S., Shinohara, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD9+is+a+surface+marker+on+mouse+and+rat+male+germline+stem+cells.">CD9 is a surface marker on mouse and rat male germline stem cells.</a> Biology of Reproduction. 70 (1), 70-70 (2004).</li><li>Ryu, B. Y., Orwig, K. E., Oatley, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+aging+and+niche+microenvironment+on+spermatogonial+stem+cell+self-renewal.">Effects of aging and niche microenvironment on spermatogonial stem cell self-renewal.</a> Stem Cells. 24 (6), 1505-1505 (2006).</li><li>Costoya, J. A., Hobbs, R. M., Barna, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Essential+role+of+Plzf+in+maintenance+of+spermatogonial+stem+cells.">Essential role of Plzf in maintenance of spermatogonial stem cells.</a> Nature Genetics. 36 (6), 653-653 (2004).</li><li>Morrow, C. M., Hostetler, C. E., Griswold, M. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ETV5+is+required+for+continuous+spermatogenesis+in+adult+mice+and+may+mediate+blood+testes+barrier+function+and+testicular+immune+privilege.">ETV5 is required for continuous spermatogenesis in adult mice and may mediate blood testes barrier function and testicular immune privilege.</a> Annals of the New York Academy of Sciences. 1120, 144-144 (2007).</li><li>Zeng, W., Snedaker, A. K., Megee, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preservation+and+transplantation+of+porcine+testis+tissue.">Preservation and transplantation of porcine testis tissue.</a> Reproduction, Fertility and Development. 21 (3), 489-489 (2009).</li><li>Jahnukainen, K., Ehmcke, J., Hergenrother, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+cold+storage+and+cryopreservation+of+immature+non-human+primate+testicular+tissue+on+spermatogonial+stem+cell+potential+in+xenografts.">Effect of cold storage and cryopreservation of immature non-human primate testicular tissue on spermatogonial stem cell potential in xenografts.</a> Human Reproduction. 22 (4), 1060-1060 (2007).</li><li>Rathi, R., Zeng, W., Megee, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Maturation+of+testicular+tissue+from+infant+monkeys+after+xenografting+into+mice.">Maturation of testicular tissue from infant monkeys after xenografting into mice.</a> Endocrinology. 149 (10), 5288-5288 (2008).</li><li>Honaramooz, A., Li, M. W., Penedo, M. 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No hay conflictos de interés declarado.

1. El transplante de células germinales Germen de trasplante de células proporciona el ensayo sólo funcional para la confirmación inequívoca de la presencia de células madre de espermatogonias (SSC) en una población celular. SSC Sólo en casa pueden y colonizar el nicho de cooperación Sur-Sur en la membrana basal e iniciar los donantes derivado de la espermatogénesis. El transplante de células germinales ha permitido estudiar y manipular las ESC de una manera sin precedentes. La técnica ha sido utilizada para producir animales transgénicos a través de la manipulación genética de las ESC 4; para dilucidar el patrón, la eficiencia y la cinética de la colonización SSC 3,8; para estudiar las vías de señalización que regulan la CSE auto-renovación y diferenciación 9,10; para caracterizar marcadores de superficie en las ESC para su identificación 22,23, estudiar el entorno de nicho para las ESC 6,7,24. Además, el trasplante recíproco ha sido empleada para investigar si un fenotipo de infertility se originó a partir de un defecto en las células de Sertoli o en 25,26 células germinales. Para el trasplante de trabajar de manera eficiente, la elección y el tratamiento de los animales receptores es importante. Los beneficiarios deben ser ya sea genéticamente compatible a los donantes o inmunosupresión. Los beneficiarios también deben carecer de la espermatogénesis endógena: o bien debido a una mutación, como en W / v los ratones, o infértil como resultado del agotamiento de las células germinales por irradiación o fármacos quimioterápicos como el busulfán. Además, una buena preparación de suspensiones de células donantes y de aptitud, de procedimiento de trasplante son importantes para el éxito de la técnica también. El transplante de células germinales tiene sus propias limitaciones. No hay tiempos de lectura de espera de los resultados. El análisis de los testículos receptores tiene que esperar por lo menos dos meses, como el restablecimiento completo de la espermatogénesis en los receptores de otra manera infértiles que ocurre dos meses después del trasplante 3. Se isa cualitativa o semi-cuantitativa ensayo debido a la inyección de grandes variaciones en el número de células y el grado de supresión de la célula receptora germen. Aunque el concepto de trasplante de células germinales se ha adaptado a otras especies animales, el procedimiento en sí es técnicamente diferente y algo más difícil en animales no roedores como resultado de las diferencias anatómicas entre las especies 11. 2. Testículo tejido xenoinjerto Tejido Testículo xenoinjerto obras a través de muchas especies de mamíferos y de donantes es una técnica relativamente sencilla. Como en otros tipos de trasplantes, la colección más pronto después de que el tejido se transplanta la oportunidad más grande de éxito. Por lo tanto, la preservación y manipulación de los tejidos desde la recolección hasta el trasplante es importante. Sin embargo, en nuestro tejido testicular experiencia no requieren un tratamiento especial diferente al que se mantiene refrigerado. Tejido Testículo puede mantenerse a temperatura del refrigerador hasta 24 a 36 h,y, a continuación fragmentos se pueden preparar para el trasplante. Además, fragmentos de testículos frescos puede ser mantenida en medio de cultivo estándar a 4 ° C antes del trasplante durante la noche sin un efecto notable sobre el resultado injerto 27. Tejido Testículo también pueden ser criopreservados si almacenamiento a largo plazo se desea. Estudios realizados en 13 cabras, cerdos 13,27, y el mono 28 han demostrado que la congelación y posterior descongelación de tejido testicular no afecta significativamente su capacidad para desarrollar y producir esperma después de ectópico xenoinjertos en ratones. Criopreservación exitosa de tejido testicular se puede lograr mediante automatizado-congelación 28 o convencional lento-congelación en un baño de alcohol 13,27, utilizando DMSO como crioprotector en medio estándar de cultivo de tejidos que contiene FBS. Para el transplante, criopreservados tejido testicular es entonces descongelada por métodos estándar y posteriormente se lavaron en medio de cultivo antes del trasplante 27. Una vez que el TISSue ha sido trasplantado el ratón receptor sirve como in vivo incubadora y no se requieren mayores intervenciones. Sin embargo, en algunos casos la suplementación con gonadotropinas exógenas que sean necesarios; tejido testicular de 6 meses de edad, los monos rhesus se requiere la inyección de los ratones receptores por vía subcutánea con 10 UI de hCG dos veces por semana para lograr la espermatogénesis completa en 6-7 meses 29. Como se mencionó anteriormente, el mejor resultado se obtiene cuando el tejido a partir de los varones recién nacidos se utiliza. El tejido de los hombres en el que las células germinales están presentes postmeióticas muestra una tendencia a degenerar. Sin embargo, con animales inmaduros recapitulación completa de desarrollo de los testículos es posible y tiene numerosas aplicaciones clínicas y de investigación. En un entorno clínico, tejido testicular xenoinjerto puede ser utilizado para preservación de la fertilidad, particularmente en los machos inmaduros en el que la recuperación de espermatozoides no es una opción. Pequeñas piezas en forma de biopsias se pueden recoger y se congelan para almacenamiento a largo plazo. Cuando desIRED, los fragmentos pueden ser descongelados y se injerta en ratones 27,28. Otra alternativa es la criopreservación de los espermatozoides que se recogerá a partir de xenoinjertos. La microinyección con espermatozoides congelados-snap de xenoinjertos de testículo de cerdo como resultado la generación de embriones morfológicamente normales, aunque en una menor eficiencia en comparación con los testículos, epidídimo o eyaculado espermatozoides 27. Después de los tejidos ha desarrollado, puede ser recogida para la recolección de semen y el esperma se puede utilizar para producir embriones in vitro 13,16,30. Una limitación de este, sin embargo, es el hecho de que el esperma resultante no someterse a la maduración epididimaria y por lo tanto requieren ICSI para la fertilización. Por lo tanto, el uso de xenoinjertos derivado del esperma para la fertilización se limita a las especies en las que la ICSI se ha establecido. En la investigación, el tejido testicular xenoinjerto es una alternativa atractiva para estudiar el desarrollo testicular y la espermatogénesis de las especies grandes en un modelo animal. Por ejemplo, untestículo de un único donante puede ser trasplantado a varios ratones. Los ratones receptores a continuación, pueden estar expuestos a diferentes tratamientos, y / o sacrificadas en diferentes puntos temporales para la recolección de xenoinjerto. Esto no sólo elimina los efectos de los donantes, sino que también reduce el número de machos de gran tamaño requieren para un experimento o estudio. Esto es particularmente importante en los animales grandes, donde los estudios con numerosos machos son logísticamente difícil y costoso, y puede llevar a limitaciones éticas, en particular en los primates. Sin embargo, las aplicaciones de xenoinjerto tejido testicular son limitados como la manipulación de tipos de células específicas antes del trasplante no es fácilmente posible y la eficiencia de la espermatogénesis es baja en especie donante ciertas 14.

<table border="1"><tbody><tr><td> Nombre del reactivo </td><td> Empresa </td><td> Número de catálogo </td></tr><tr><td> La colagenasa (tipo IV) </td><td> Sigma </td><td> C5138 </td></tr><tr><td> Tripsina-EDTA </td><td> Invitrogen </td><td> 25200-056 </td></tr><tr><td> DNaseI </td><td> Sigma </td><td> DN25 </td></tr><tr><td> DMEM </td><td> Invitrogen </td><td> 31053-028 </td></tr><tr><td> Trypan mancha azul </td><td> Invitrogen </td><td> 15250-061 </td></tr><tr><td> Malla de nylon filtro de células </td><td> BD Biosciences </td><td> 352.340 (40 micromolar) 352 350 (70μm) </td></tr><tr><td> Busulfano </td><td> Sigma </td><td> B2635 </td></tr><tr><td> De pared delgada capilares de vidrio </td><td> Mundial de instrumentos de precisión </td><td> TW 100-3 </td></tr><tr><td> BD intramedic tubo plyethylene (PE100) </td><td> BD </td><td> CA-63018-725 </td></tr><tr><td> Ethicon 6-0 sutura de seda </td><td> Ethicon </td><td> 706G </td></tr><tr><td> Clips de la herida </td><td> BD </td><td> 427631 </td></tr><tr><td> Sigmacote </td><td> Sigma </td><td> SL2 </td></tr><tr><td> X-gal </td><td> Sigma </td><td> B4252 </td></tr><tr><td> Ferrocianuro de potasio </td><td> Sigma </td><td> P9387 </td></tr><tr><td> Ferricianuro de potasio </td><td> Sigma </td><td> P3667 </td></tr><tr><td> cloruro de magnesio </td><td> Sigma </td><td> 208337 </td></tr><tr><td> sodio desoxicolato </td><td> Sigma </td><td> D6750 </td></tr><tr><td> N, N-Dimetilformamida </td><td> Sigma </td><td> D4551 </td></tr><tr><td> Igepal CA-630 </td><td> Sigma </td><td> 18896 </td></tr></tbody></table>

germ cell transplantation and testis tissue xenografting in mice

El transplante de células germinales fue desarrollado por el Dr. Ralph Brinster y sus colegas de la Universidad de Pennsylvania en 1994 1,2. Estos estudios innovadores mostraron que la microinyección de células germinales de los ratones donantes fértiles en los túbulos seminíferos de ratones infértiles receptores de donantes en los resultados derivados de la espermatogénesis y la producción de esperma por parte del animal receptor 2. El uso de machos donantes que transporten la bacteriana β-galactosidasa la identificación de genes permitido de donante-deriva la espermatogénesis y la transmisión de la haplotipo donante a la descendencia por 1 los animales receptores. Sorprendentemente, después de un trasplante en el lumen de los túbulos seminíferos, las células germinales trasplantados fueron capaces de pasar del compartimento luminal de la membrana basal, donde se encuentran las espermatogonias 3. En general se acepta que las ESC sólo son capaces de colonizar el nicho y la espermatogénesis volver a establecerse en los testículos receptores. Por lo tanto, de células germinalesel trasplante ofrece un enfoque funcional para estudiar el nicho de células madre en los testículos y caracterizar supuestas células madre de espermatogonias. Hasta la fecha, el trasplante de células germinales se utiliza para dilucidar la biología básica de células madre, para producir animales transgénicos a través de la manipulación genética de células germinales antes del trasplante 4,5, para estudiar células de Sertoli-germen de interacción celular 6,7, SSC homing y la colonización 3, 8, así como la CSE auto-renovación y diferenciación 9,10. El trasplante de células germinales es también factible en especies de gran tamaño 11. En éstas, las principales aplicaciones son la preservación de la fertilidad, la difusión de la genética de élite en las poblaciones animales, y la generación de animales transgénicos como el estudio de la espermatogénesis y la biología de piel a piel con esta técnica es logísticamente más difícil y caro que en los roedores. El trasplante de células germinales de especies de gran tamaño en los túbulos seminíferos de ratones resulta en colonizatde iones de las células del donante y la expansión espermatogonias, pero no en su diferenciación completa presumiblemente debido a la incompatibilidad del compartimiento célula receptora somática con las células germinales de especies filogenéticamente distantes 12. Un enfoque alternativo es el trasplante de las células germinales de especies de gran tamaño, junto con su entorno compartimento somática. Estamos por primera vez en 2002, que pequeños fragmentos de tejido testicular de los machos inmaduros trasplantadas bajo la piel dorsal de ratones inmunodeficientes son capaces de sobrevivir y tener un desarrollo completo con la producción de esperma fertilización competente 13. Desde entonces, tejido testicular xenoinjerto se ha demostrado para tener éxito en muchas especies y ha surgido como una alternativa valiosa para estudiar el desarrollo testicular y la espermatogénesis de los animales grandes en ratones 14.

Watch this Scientific Journal Video about Germ Cell Transplantation and Testis Tissue Xenografting in Mice at JoVE.com

Germ Cell Transplantation and Testis Tissue Xenografting in Mice

Los protocolos para el trasplante de células germinales de testículo y el xenotrasplante de tejido se describen. Germen de los resultados de trasplante de células en donantes derivado de la espermatogénesis en los testículos receptores y representa un ensayo de reconstitución funcional para la identificación de células madre de espermatogonias (SSC). Tejido testicular xenoinjerto reproduce desarrollo de los testículos y la espermatogénesis de las especies de los distintos donantes en los ratones receptores.

Germen de Trasplante de Células y Tejidos Testículos xenotrasplante en ratones

Germ cell transplantation was developed by Dr. Ralph Brinster and colleagues at the University of Pennsylvania in 19941,2. These ground-breaking studies ...

germ-cell-transplantation-and-testis-tissue-xenografting-in-mice

Nanyang Technological University

Research

JoVE Journal

Biology

29.7K vistas.  University of Calgary. Los protocolos para el trasplante de células germinales de testículo y el xenotrasplante de tejido se describen. Germen de los resultados de trasplante de células en donantes derivado de la espermatogénesis en los testículos receptores y representa un ensayo de reconstitución funcional para la identificación de células madre de espermatogonias (SSC). Tejido testicular xenoinjerto reproduce desarrollo de los testículos y la espermatogénesis de las especies de los...

Video: Germ Cell Transplantation and Testis Tissue Xenografting in Mice

Isolation and Transplantation of Hematopoietic Stem Cells (HSCs)

Isolation and Transplantation of Hematopoietic Stem Cells HSCs

I am Christina Ceso. I am a postdoc in David's Den lab and I work on the hematopoietic stem cells. Today we are going to purify long-term recuperating hematopoietic stem cells and we'll transplant them into a mouse.We start by spraying the mice with alcohol so that first of all, the mind starts sterilized and also the hair doesn't interfere with the dissection. We use PBS with 2%serum for the dissection. I cut the back skin and I pull the skin apart in order to expose the tissue.In order to isolate the tibia, I hold the tibia with tweezers. I cut the tendon on top of the knee and I cut the muscles below the knee and after that I cut through the knee so that the TBI is not connected to the rest of the limb anymore and I pull in order to isolate it. I then hold the TB upside down and with the scissors I separate the foot from the tibia In order to obtain the femur.I cut the muscles around the femur and then I dislocate the femur from the hip. In order to isolate the hip, I cut the muscle around the hip bone on the side of the tail of the mouse and then I pull the hip away from the body of the mouth In order to isolate the spine. I cut through the tail as close as I can to the beginning of the back and then I cut on the two sides of the spine and below the spine, trying to stay as close as possible to the spine so that the peritoneum is not cut and the intestine is left untouched.A first round of cleaning of the bones is done with a scalpel, which is used to scrape the bone, the muscles away from the bone. The scalpel is good to clean the femurs, the hip and the spine. In order to clean the tibia, I hold them with forceps and I use the forceps to remove as much tissue as possible.A second round of cleaning is done using clean wipe to completely clean the bones outta the muscle, and I use the F wipe to clean the tibia, the femurs and the hips. So this is how bones look. After cleaning, I prefer 50 amount tubes with filters on top and I transfer the bones into the mortar.I add the section media and I crush the bones ask of the first round of crashing of the bones. I piped the mixture in order to release as many styles as possible into solution and reduce clumps. I transferred the mixture on the tubes through the filters and this is what the bone fragments look like after the first round of crushing.So I add more dissection medium to the bone fragments and I flash them again. I transferred the seline mixture to the tubes through the filters and at this point the remaining bone fragments are white and there is no bone marrow left. The tubes are filled with PBS 2%serum and in order to have them all with the same weight so that they're balanced in the centrifuge, but also in order to wash the filters so that we obtain as many cells as possible, I then centrifuge the cell mixture and after centrifugation, the palt includes the bone marrow cells.I aspirate the medium and I move back and forward the tube on the rack so that the pelle is becomes loose and fewer clamps are formed. When I add medium, at this point I add one ml of medium per tube and I ics since I'm sorting hematopoietic stem cells. Later on, I'm going to store an ALI output of total bone marrow sizes at this point, which I will use later for the fact single color control.I add lineage antibody cocktail. I ordered the samples to mix them well and I invaded four degrees for 15 minutes. In the meantime, I start preparing the columns for the lineage division.I put the columns on the magnet and I prepare Ian tubes under the columns. I also prepared the gas PBS using aster flip filter and attaching it to the vacuum so that all the bubbles of air move in the top part of the filter. I then add three ml of the gas DBS to each column in order for the column to become wet.After the incubation with the antibodies, I add medium to the cell samples and I centrifuge them in order to remove the excess of antibodies. After the centrifugation, the stain cells are in the pallet. I aspirate the medium and I suspend the pallet in one mile of the gas PBSI Add the strip tab beans, I mix the cells and I incubate for 15 minutes at four degrees.After the incubation, I put new elucian tubes under the columns. I add two ml of PBS to each tube with the cells and I transferred the cell mixture to the column through a 40 micron filter. I wash the tubes with more medium in order to collect all the cells remaining and I apply the remaining medium through the filters to the columns.The progenitor cells lineage low are alluded into the collection views. I pulled the luted samples and I sent tofu them. So after the centrifugation, the depleted cells are in a white pate.I aspirate the medium and re suspend the cells. I store an adequate of the depleted cells and I add the antibodies to the cell mixture for the sorting and also to all the single color controls. The antibodies are incubated in that with the size for 15 minutes in the fridge.After the ation, I add medium to the cells and and centrifuge them to remove the ex excess of antibodies. After the centrifugation, the cells are in the pt, I aspirate the media that I suspend the cells and I transfer the cells into fox tubes with a blue filter. At this point, the cells are ready to be sorted.I place, I place the mouse under a heating lamp for a few minutes so that the veins dilate and they are more easily seen. When preparing the syringe, you have to be careful to eliminate all the bubbles from the, the mixture that is in the syringe and then you bend the needle at 90 degrees. I put the mouse under a glass cup with a weight on top so that it can run away.I sterilize the tail with the alcohol pad so that the site of injection is sterile, but also it's easier to identify the vein. If you look at the tail of the mouse from the top in the middle and top of the tail, there is an artery while on the two sides there are the two veins and we inject the cells in one of the two veins. I insert the needle into the vein and I inject following injection.It is to wait for a couple of seconds before removing the needle, the needle, and after that I clean the side of injection. This is a representation of the syringe with the ben needle bent at 90 degrees with the knee, the at this ankle compared to the tail, which makes the injection the easiest. When you injecting the tail of the mouse, you have to keep in mind that the tail vein is extremely superficial, so really this is the orientation of the needle compared to the tail.And it looks like you will just keep sliding on top of the tail, but actually you will get into the tail then. I am Christina Ceso. I am a post in David Kaden lab, and I work on the hematopoietic stem cells.I usually use for animals to start with, and I had more variability at the beginning, but once you become consistent with your methods, I consistently get about 50, 000 to 60, 000 stem cells out for mice. I did my PhD in London with Dr.Fiona Wat working on derma stem cells. After that, I just wanted to have a wider knowledge of adult stem cells in various tissues, and so I decided to move to David Kaden lab to work on hematopoietic stem cells, mainly because the things that are known about hematopoietic stem cells are the things that are not known for the epidermic stem cells and a number of assays that can be done with epi.Epidermal stem cells are not really done yet with the hematopoietic stem cells, and so at this point I'm trying to put together the, the knowledge from the two different fields and ultimately I'm interested in the study of the mechanism to regulate adult tissue sensors in general, so not just the epidermis or the stem cells, but also different tissues because there are, there are similar mechanism that is, it's always the same genes that are involved in the regulation that just interact with each other in different ways, and it's just interesting to understand what makes each stem cell be a stem, but then ultimately a stem cell in a different tissue. So giving rise to a different protein.

Aislamiento y trasplante de células madre hematopoyéticas (HSC)

Investigación

Biología

Heterotopic Heart Transplantation in Mice

The mouse heterotopic heart transplantation has been used widely since it was introduced by Drs. Corry and Russell in 1973. It is particularly valuable for studying rejection and immune response now that newer transgenic and gene knockout mice are available, and a large number of immunologic reagents have been developed. The heart transplant model is less stringent than the skin transplant models, although technically more challenging. We have developed a modified technique and have completed over 1000 successful cases of heterotopic heart transplantation in mice. When making anastomosis of the ascending aorta and abdominal aorta, two stay sutures are placed at the proximal and distal apexes of recipient abdominal aorta with the donor s ascending aorta, then using 11-0 suture for anastomosis on both side of aorta with continuing sutures. The stay sutures make the anastomosis easier and 11-0 is an ideal suture size to avoid bleeding and thrombosis.
When making anastomosis of pulmonary artery and inferior vena cava, two stay sutures are made at the proximal apex and distal apex of the recipient s inferior vena cava with the donor s pulmonary artery. The left wall of the inferior vena cava and donor s pulmonary artery is closed with continuing sutures in the inside of the inferior vena cava after, one knot with the proximal apex stay suture the right wall of the inferior vena cava and the donor s pulmonary artery are closed with continuing sutures outside the inferior vena cave with 10-0 sutures. This method is easier to perform because anastomosis is made just on the one side of the inferior vena cava and 10-0 sutures is the right size to avoid bleeding and thrombosis. In this article, we provide details of the technique to supplement the video.

The mouse heterotopic heart transplantation model has been proven by many investigators to be an important method for studying mechanisms of rejection and immune response. However, the techniques involved are still challenging. By modifying standard techniques we have had success with more than 1000 transplants.

El trasplante cardíaco heterotópico en ratones

The mouse heterotopic heart transplantation has been used widely since it was introduced by Drs. Corry and Russell in 1973. It is particularly valuable ...

Small Bowel Transplantation In Mice

Since 1990, the development of tacrolimus-based immunosuppression and improved surgical techniques, the increased array of potent immunosuppressive medications, infection prophylaxis, and suitable patient selection helped improve actuarial graft and patient survival rates for all types of intestine transplantation. Patients with irreversible intestinal failure and complications of parenteral nutrition should now be routinely considered for small intestine transplantation. However, Survival rates for small intestinal transplantation have been slow to improve compares increasingly favorably with renal, liver, heart and lung. The small bowel transplantation is still unsatisfactory compared with other organs. Further progress may depend on better understanding of immunology and physiology of the graft and can be greatly facilitated by animal models. A wider use of mouse small bowel transplantation model is needed in the study of immunology and physiology of the transplantation gut as well as efficient methods in diagnosing early rejection. However, this model is limited to use because the techniques involved is an extremely technically challenging. We have developed a modified technique. When making anastomosis of portal vein and inferior vena cava, two stay sutures are made at the proximal apex and distal apex of the recipient s inferior vena cava with the donor s portal vein. The left wall of the inferior vena cava and donor s portal vein is closed with continuing sutures in the inside of the inferior vena cava after, after one knot with the proximal apex stay suture the right wall of the inferior vena cava and the donor s portal vein are closed with continuing sutures outside the inferior vena cave with 10-0 sutures. This method is easier to perform because anastomosis is made just on the one side of the inferior vena cava and 10-0 sutures is the right size to avoid bleeding and thrombosis.  In this article, we provide details of the technique to supplement the video.

The mouse small bowel transplantation model has been recognized as an important tool to study mechanismes of immune rejection and screen new immunosuppressive drugs. However, this model is limited to use because the techniques involved is an extremely technically challenge. Now we introduce the modified technique.

Trasplante de intestino delgado en ratones

Since 1990, the development of tacrolimus-based immunosuppression and improved surgical techniques, the increased array of potent immunosuppressive ...

Actin Co-Sedimentation Assay; for the Analysis of Protein Binding to F-Actin

The actin cytoskeleton within the cell is a network of actin filaments that allows the movement of cells and cellular processes, and that generates tension and helps maintains cellular shape.  Although the actin cytoskeleton is a rigid structure, it is a dynamic structure that is constantly remodeling.  A number of proteins can bind to the actin cytoskeleton.  The binding of a particular protein to F-actin is often desired to support cell biological observations or to further understand dynamic processes due to remodeling of the actin cytoskeleton. The actin co-sedimentation assay is an in vitro assay routinely used to analyze the binding of specific proteins or protein domains with F-actin.  The basic principles of the assay involve an incubation of the protein of interest (full length or domain of) with F-actin, ultracentrifugation step to pellet F-actin and analysis of the protein co-sedimenting with F-actin.  Actin co-sedimentation assays can be designed accordingly to measure actin binding affinities and in competition assays.

Proteins bind to filamentous actin (F-actin) through distinct actin binding modules. In this video we demonstrate the procedure of actin co-sedimentation, which is an in vitro assay routinely used to analyze proteins or specific domains that bind F-actin.

Actina Co-sedimentación de ensayo, pues el análisis de proteína de unión a la F-actina

The actin cytoskeleton within the cell is a network of actin filaments that allows the movement of cells and cellular processes, and that generates ...

Generation of Human CD40-activated B cells

CD40-activated B cells (CD40-B cells) have been identified as an alternative source of immuno-stimulatory antigen-presenting cells (APC) for cancer immunotherapy 1-3. Compared to Dendritic cells (DCs), the best characterized APC, CD40-B cells have several distinct biological and technical properties. Similar to DCs, B cells show an increased expression of MHC and co-stimulatory molecules (Fig.1b), exhibit a strong migratory capacity and present antigen presentation efficiently to T cells, after stimulation with interleukin-4 and CD40 ligand (CD40L). However, in contrast to immature or mature DCs, CD40-B cells express the full lymph node homing triad consisting of CD62L, CCR7/CXCR4, and leukocyte function antigen-1 (LFA1, CD11a/CD18), necessary for homing to secondary lymphoid organs (Fig.1a) 3. CD40-B cells can be generated without difficulties from very small amounts of peripheral blood which can be further expanded in vitro to very large amounts of highly-pure CD40-B cells (&gt;109 cells per patient) from healthy donors as well as cancer patients (Fig.1c,d) 1,4. 
In this protocol we demonstrate how to obtain fully activated CD40-B cells from human PBMC. Key molecules for the cell culture are CD40 ligand, interleukin-4 (IL-4) and cyclosporin A (CsA), which are replenished in a 3-4 day culture cycle. For laboratory purposes CD40-stimulation is provided by NIH/3T3 cells expressing recombinant human CD40 ligand (tCD40L NIH/3T3) 5. To avoid contamination with non-transfected cells, expression of the human CD40 ligand on the transfectants has to be checked regularly (Fig.2). 
After 14 days CD40-B cell cultures consist of more than 95% pure B cells and an expansion of CD40-B cells over 65 days is frequently possible without any loss of function 1, 4. CD40-B cells efficiently take up, process and present antigens to T cells 6. They do not only prime na&#970;ve, but also expand memory T cells 7,8. CD40-activated B cells can be used to study B-cell activation, differentiation and function. Moreover, they represent a promising tool for therapeutic or preventive vaccination against tumors 9.

In this video we present the ex vivo generation and expansion of human CD40-activated B cells (CD40-B) from peripheral blood mononuclear cells (PBMC) by stimulation with CD40 ligand and interleukin-4.

Generación de humanos CD40 activado por células B

CD40-activated B cells (CD40-B cells) have been identified as an alternative source of immuno-stimulatory antigen-presenting cells (APC) for cancer ...

Tissue Targeted Embryonic Chimeras: Zebrafish Gastrula Cell Transplantation

Certain fundamental questions in the field of developmental biology can only be answered when cells are placed in novel environments or when small groups of cells in a larger context are altered.  Watching how one cell interacts with and behaves in a unique environment is essential to characterizing cell functions.  Determining how the localized misexpression of a specific protein influences surrounding cells provides insightful information on the roles that protein plays in a variety of developmental processes.  Our lab uses the zebrafish model system to uniquely combine genetic approaches with classical transplantation techniques to generate genotypic or phenotypic chimeras.  We study neuron-glial cell interactions during the formation of forebrain commissures in zebrafish. This video describes a method that allows our lab to investigate the role of astroglial populations in the diencephalon and the roles of specific guidance cues that influence projecting axons as they cross the midline. Due to their transparency zebrafish embryos are ideal models for this type of ectopic cell placement or localized gene misexpression. Tracking transplanted cells can be accomplished using a vital dye or a transgenic fish line expressing a fluorescent protein. We demonstrate here how to prepare donor embryos with a vital dye tracer for transplantation, as well as how to extract and transplant cells from one gastrula staged embryo to another.  We present data showing ectopic GFP+ transgenic cells within the forebrain of zebrafish embryos and characterize the location of these cells with respect to forebrain commissures.  In addition, we show laser scanning confocal timelapse microscopy of Alexa 594 labeled cells transplanted into a GFP+ transgenic host embryo.  These data provide evidence that gastrula staged transplantation enables the targeted positioning of ectopic cells to address a variety of questions in Developmental Biology.

Zebrafish cell transplantation enables the combination of genetics and embryology to generate tissue specific chimeras. This video demonstrates gastrula staged cell transplantations that have allowed our lab to investigate the roles of astroglial populations and specific guidance cues during commissure formation in the forebrain.

Tejido diana quimeras embrionarias: pez cebra Gástrula Trasplante de células

Certain fundamental questions in the field of developmental biology can only be answered when cells are placed in novel environments or when small groups ...

Heterotopic and Orthotopic Tracheal Transplantation in Mice used as Models to Study the Development of  Obliterative Airway Disease

Obliterative airway disease (OAD) is the major complication after lung transplantations that limits long term survival (1-7).
To study the pathophysiology, treatment and prevention of OAD, different animal models of tracheal transplantation in rodents have been developed (1-7). Here, we use two established models of trachea transplantation, the heterotopic and orthotopic model and demonstrate their advantages and limitations.
For the heterotopic model, the donor trachea is wrapped into the greater omentum of the recipient, whereas the donor trachea is anastomosed by end-to-end anastomosis in the orthotopic model.
In both models, the development of obliterative lesions histological similar to clinical OAD has been demonstrated (1-7).
This video shows how to perform both, the heterotopic as well as the orthotopic tracheal transplantation technique in mice, and compares the time course of OAD development in both models using histology.

This video shows and compares two experimental models to study the development of obliterative airway disease (OAD) in mice, the heterotopic and orthotopic tracheal transplantation model.

El trasplante heterotópico traqueal y ortotópico en ratones utilizados como modelos para estudiar el desarrollo de la enfermedad de las vías respiratorias obliterante

Obliterative airway disease (OAD) is the major complication after lung transplantations that limits long term survival (1-7).
To study the ...

Planarian Immobilization, Partial Irradiation, and Tissue Transplantation

The planarian, a freshwater flatworm, has proven to be a powerful system for dissecting metazoan regeneration and stem cell biology1,2. Planarian regeneration of any missing or damaged tissues is made possible by adult stem cells termed neoblasts3. Although these stem cells have been definitively shown to be pluripotent and singularly capable of reconstituting an entire animal4, the heterogeneity within the stem cell population and the dynamics of their cellular behaviors remain largely unresolved. Due to the large number and wide distribution of stem cells throughout the planarian body plan, advanced methods for manipulating subpopulations of stem cells for molecular and functional study in vivo are needed.
Tissue transplantation and partial irradiation are two methods by which a subpopulation of planarian stem cells can be isolated for further study. Each technique has distinct advantages. Tissue transplantation allows for the introduction of stem cells, into a na&iuml;ve host, that are either inherently genetically distinct or have been previously treated pharmacologically. Alternatively, partial irradiation allows for the isolation of stem cells within a host, juxtaposed to tissue devoid of stem cells, without the introduction of a wound or any breech in tissue integrity. Using these two methods, one can investigate the cell autonomous and non-autonomous factors that control stem cell functions, such as proliferation, differentiation, and migration.
Both tissue transplantation5,6 and partial irradiation7 have been used historically in defining many of the questions about planarian regeneration that remain under study today. However, these techniques have remained underused due to the laborious and inconsistent nature of previous methods. The protocols presented here represent a large step forward in decreasing the time and effort necessary to reproducibly generate large numbers of grafted or partially irradiated animals with efficacies approaching 100 percent. We cover the culture of large animals, immobilization, preparation for partial irradiation, tissue transplantation, and the optimization of animal recovery. Furthermore, the work described here demonstrates the first application of the partial irradiation method for use with the most widely studied planarian, Schmidtea mediterranea. Additionally, efficient tissue grafting in planaria opens the door for the functional testing of subpopulations of na&iuml;ve or treated stem cells in repopulation assays, which has long been the gold-standard method of assaying adult stem cell potential in mammals8. Broad adoption of these techniques will no doubt lead to a better understanding of the cellular behaviors of adult stem cells during tissue homeostasis and regeneration.

An effective method for grafting tissue of defined and consistent size between planaria is described. Also included is a description of how the immobilization technique used for transplantation can be adapted, in conjunction with lead shields, for the partial irradiation of live animals.

La inmovilización de las planarias, irradiación parcial, y el trasplante de tejido

The planarian, a freshwater flatworm, has proven to be a powerful system for dissecting metazoan regeneration and stem cell biology1,2. Planarian ...

Studying Proteolysis of Cyclin B at the Single Cell Level in Whole Cell Populations

Equal distribution of chromosomes between the two daughter cells during cell division is a prerequisite for guaranteeing genetic stability 1. Inaccuracies during chromosome separation are a hallmark of malignancy and associated with progressive disease 2-4. The spindle assembly checkpoint (SAC) is a mitotic surveillance mechanism that holds back cells at metaphase until every single chromosome has established a stable bipolar attachment to the mitotic spindle1. The SAC exerts its function by interference with the activating APC/C subunit Cdc20 to block proteolysis of securin and cyclin B and thus chromosome separation and mitotic exit. Improper attachment of chromosomes prevents silencing of SAC signaling and causes continued inhibition of APC/CCdc20 until the problem is solved to avoid chromosome missegregation, aneuploidy and malignant growths1.
Most studies that addressed the influence of improper chromosomal attachment on APC/C-dependent proteolysis took advantage of spindle disruption using depolymerizing or microtubule-stabilizing drugs to interfere with chromosomal attachment to microtubules. Since interference with microtubule kinetics can affect the transport and localization of critical regulators, these procedures bear a risk of inducing artificial effects 5.
To study how the SAC interferes with APC/C-dependent proteolysis of cyclin B during mitosis in unperturbed cell populations, we established a histone H2-GFP-based system which allowed the simultaneous monitoring of metaphase alignment of mitotic chromosomes and proteolysis of cyclin B 6.
To depict proteolytic profiles, we generated a chimeric cyclin B reporter molecule with a C-terminal SNAP moiety 6 (Figure 1). In a self-labeling reaction, the SNAP-moiety is able to form covalent bonds with alkylguanine-carriers (SNAP substrate) 7,8 (Figure 1). SNAP substrate molecules are readily available and carry a broad spectrum of different fluorochromes. Chimeric cyclin B-SNAP molecules become labeled upon addition of the membrane-permeable SNAP substrate to the growth medium 7 (Figure 1). Following the labeling reaction, the cyclin B-SNAP fluorescence intensity drops in a pulse-chase reaction-like manner and fluorescence intensities reflect levels of cyclin B degradation 6 (Figure 1). Our system facilitates the monitoring of mitotic APC/C-dependent proteolysis in large numbers of cells (or several cell populations) in parallel. Thereby, the system may be a valuable tool to identify agents/small molecules that are able to interfere with proteolytic activity at the metaphase to anaphase transition. Moreover, as synthesis of cyclin B during mitosis has recently been suggested as an important mechanism in fostering a mitotic block in mice and humans by keeping cyclin B expression levels stable 9,10, this system enabled us to analyze cyclin B proteolysis as one element of a balanced equilibrium 6.

Metaphase to anaphase transition is triggered through anaphase-promoting complex (APC/C)-dependent ubiquitination and subsequent destruction of cyclin B. Here, we established a system which, following pulse-chase labeling, allows monitoring cyclin B proteolysis in entire cell populations and facilitates the detection of interference by the mitotic checkpoint.

El estudio de la proteólisis de ciclina B en el nivel de células individuales en poblaciones de células enteras

Equal distribution of chromosomes between the two daughter cells during cell division is a prerequisite for guaranteeing genetic stability 1. Inaccuracies ...

Isolation, Culture, and Transplantation of Muscle Satellite Cells

Muscle satellite cells are a stem cell population required for postnatal skeletal muscle development and regeneration, accounting for 2-5% of sublaminal nuclei in muscle fibers. In adult muscle, satellite cells are normally mitotically quiescent. Following injury, however, satellite cells initiate cellular proliferation to produce myoblasts, their progenies, to mediate the regeneration of muscle. Transplantation of satellite cell-derived myoblasts has been widely studied as a possible therapy for several regenerative diseases including muscular dystrophy, heart failure, and urological dysfunction. Myoblast transplantation into dystrophic skeletal muscle, infarcted heart, and dysfunctioning urinary ducts has shown that engrafted myoblasts can differentiate into muscle fibers in the host tissues and display partial functional improvement in these diseases. Therefore, the development of efficient purification methods of quiescent satellite cells from skeletal muscle, as well as the establishment of satellite cell-derived myoblast cultures and transplantation methods for myoblasts, are essential for understanding the molecular mechanisms behind satellite cell self-renewal, activation, and differentiation. Additionally, the development of cell-based therapies for muscular dystrophy and other regenerative diseases are also dependent upon these factors.

However, current prospective purification methods of quiescent satellite cells require the use of expensive fluorescence-activated cell sorting (FACS) machines. Here, we present a new method for the rapid, economical, and reliable purification of quiescent satellite cells from adult mouse skeletal muscle by enzymatic dissociation followed by magnetic-activated cell sorting (MACS). Following isolation of pure quiescent satellite cells, these cells can be cultured to obtain large numbers of myoblasts after several passages. These freshly isolated quiescent satellite cells or ex vivo expanded myoblasts can be transplanted into cardiotoxin (CTX)-induced regenerating mouse skeletal muscle to examine the contribution of donor-derived cells to regenerating muscle fibers, as well as to satellite cell compartments for the examination of self-renewal activities.

The isolation and culture of a pure population of quiescent satellite cells, a muscle stem cell population, is essential to the understanding of muscle stem cell biology and regeneration, as well as stem cell transplantation for therapies in muscular dystrophy and other degenerative diseases.&#160;

Aislamiento, cultivo y trasplante de células musculares satélite

Muscle satellite cells are a stem cell population required for postnatal skeletal muscle development and regeneration, accounting for 2-5% of sublaminal ...